The numbers 684 to 690 in roman numerals
The right column shows how each roman numeral adds up to the total.
| 684 | = | DCLXXXIV | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 − 1 |
| 685 | = | DCLXXXV | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 |
| 686 | = | DCLXXXVI | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 + 1 |
| 687 | = | DCLXXXVII | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 + 1 + 1 |
| 688 | = | DCLXXXVIII | = | 500 + 100 + 50 + 10 + 10 + 10 + 5 + 1 + 1 + 1 |
| 689 | = | DCLXXXIX | = | 500 + 100 + 50 + 10 + 10 + 10 + 10 − 1 |
| 690 | = | DCXC | = | 500 + 100 + 100 − 10 |